If you are not popping your vitamins A, C, E pills, then you really aren't part of the antioxidant in crowd.
TEN OR so years ago, few persons outside the scientific community would have heard the words "free radicals" and "antioxidants". Now its on everybody's lips and most food products now boast their antioxidant power.
So popular have these health concepts become, that even the farmers and agriculturalists are coming in on the act. Last Wednesday at a public lecture held at Eden Gardens in Kingston, they were being told about producing fruits and vegetables in a way that maximises the health promotive effects of antioxidants.
The presenter was Raymond Thomas, a Jamaican Ph.D research student at Auburn University, United States. He has been researching various fruits and vegetables and reports that the concentration of antioxidants varies with maturity, type of fruits, technique of storage, among other variables.
He reports, for instance, that the total antioxidant activity of blackberries declines as the fruit matures. Among the water melon, he states that the highest levels of antioxidant were found in the 'constitution' variety. Other varieties such as freedom, revolution, Tri-X313 and 5244.
"The rationale for this, is to help farmers to decide the best variety (of fruits and vegetables) to grow, to enhance the health status and antioxidant intake in Jamaica. These varieties can be labelled as having superior antioxidant levels, they can be sold as fresh, whole fruits and vegetables or sold as sliced fruits," Mr. Thomas said, pointing to this new approach to farming as one way to boost sales in Jamaican products world-wide.
Antioxidants (such as, vitamins A, C, E) would hardly be important, except for free radicals. What are these free radicals? In 'chemistry and physiology 101', students are taught that the human body is made up of cells which have molecules. These molecules are composed of atoms. These atoms can be further broken down into its various parts but one of its parts, the electron, is important in understanding free
radicals.
Free radicals carry an odd number of electrons or unpaired electrons. They may be formed when oxygen reacts with certain molecules. These 'abnormal' molecules are highly reactive, and can become harmful to the body; various studies link this reactive radicals to cancer, ageing and a variety of diseases. This is where the antioxidants become important; they are supposed to be the body's defence system against free radicals.
The science is well worked out but medical doctor and past president of the Medical Association of Jamaica (MAJ), Dr. Winston Davidson, who was a member of the audience at last week's public lecture, said that he was sceptical of claims that say phytochemicals and antioxidants will in fact, prevent cancer of the colon.
"It is as if the cancer is directly related to the antioxidant effect of cells in the colon. We know that oxidation is only one aspect of cancer formation... we cannot establish the cause and effect relationship. If we say that it contributes to cancer prevention then that is different," he said.
Dr. Davidson was also sceptical that the researchers could actually pinpoint when antioxidant levels were at their best in food.
"I mean you can't just stop the process of metabolism, so to identify precisely when there is optimum antioxidant in fruits and when the fruit is fit for human consumption is a challenge," he said.
Antioxidant power
- the West Indian cherry has been identified as the fruit with the second
highest amount of antioxidant
- antioxidants in fruits and vegetables include vitamin A, C, E, phenolic
acids, flavonoids, polyphenol
- carrots are good sources of beta carotene
- get vitamin C from citrus, kiwi
- great sources of vitamin E are pears, avocado
- sweet potatoes are good sources of lutein/lycopene
- antioxidants are produced in the body or derived from the diet. We have
little control over antioxidants produced in the body but we can control our
diet
- recently, there were restrictions on the use of synthetic antioxidants because
of suggestions that they may be carcinogenic.
- antioxidants are reported to act in the prevention of cardiovascular diseases,
cancers, ageing, diabetes
- lycopene reduces the risk of colon cancer by 21 per cent among male health
professionals 1995 study Gillman et al
- clinical studies indicate that antioxidants produce 40 per cent lower risk
of coronary heart
disease
